content: /*
   * Copyright 2016-present David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package hu.akarnokd.rxjava3.basetypes;
  
  import java.util.concurrent.atomic.AtomicReference;
  
  import org.reactivestreams.*;
  
  import io.reactivex.rxjava3.exceptions.Exceptions;
  import io.reactivex.rxjava3.functions.BooleanSupplier;
  import io.reactivex.rxjava3.internal.subscriptions.SubscriptionHelper;
  
  /**
   * Repeat until the supplier returns true.
   */
  final class NonoRepeatUntil extends Nono {
  
      final Nono source;
  
      final BooleanSupplier stop;
  
      NonoRepeatUntil(Nono source, BooleanSupplier stop) {
          this.source = source;
          this.stop = stop;
      }
  
      @Override
      protected void subscribeActual(Subscriber<? super Void> s) {
          source.subscribe(new RepeatUntilSubscriber(s, stop, source));
      }
  
      static final class RepeatUntilSubscriber extends BasicNonoIntQueueSubscription
      implements Subscriber<Void> {
  
          private static final long serialVersionUID = -3208438978515192633L;
  
          protected final Subscriber<? super Void> downstream;
  
          final Nono source;
  
          final BooleanSupplier stop;
  
          final AtomicReference<Subscription> upstream;
  
          volatile boolean active;
  
          boolean once;
  
          RepeatUntilSubscriber(Subscriber<? super Void> downstream,
                  BooleanSupplier stop, Nono source) {
              this.downstream = downstream;
              this.stop = stop;
              this.source = source;
              this.upstream = new AtomicReference<>();
          }
  
          @Override
          public void cancel() {
              SubscriptionHelper.cancel(upstream);
          }
  
          @Override
          public void onSubscribe(Subscription s) {
              SubscriptionHelper.replace(this.upstream, s);
              if (!once) {
                  once = true;
                  downstream.onSubscribe(this);
              }
          }
  
          @Override
          public void onNext(Void t) {
              // never called
          }
  
          @Override
          public void onError(Throwable t) {
              downstream.onError(t);
          }
  
          @Override
          public void onComplete() {
              active = false;
              subscribeNext();
          }
  
          void subscribeNext() {
              boolean b;
  
              try {
                  b = stop.getAsBoolean();
              } catch (Throwable ex) {
                  Exceptions.throwIfFatal(ex);
                  downstream.onError(ex);
                  return;
              }
  
              if (b) {
                  downstream.onComplete();
              } else {
                  if (getAndIncrement() == 0) {
                      do {
                          if (SubscriptionHelper.CANCELLED == upstream.get()) {
                              return;
                          }
  
                          if (!active) {
                              active = true;
                              source.subscribe(this);
                          }
                      } while (decrementAndGet() != 0);
                  }
              }
          }
      }
  }
  